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RELAYⓇ THERAPEUTICS Relay Therapeutics Announces Corporate Updates and Reports Second Quarter 2021 Financial Results August 12 , 2021 Company selected RLY - 2608 as PI3Ka mutant inhibitor development candidate and plans to initiate first - in - human study in the first half of 2022 RLY - 2608 potently inhibits mutants H1047X , E542X , and E545X , which affect over 100,000 patients annually in the U.S. Relay Therapeutics and EQRX enter a collaboration to discover , develop , and commercialize novel oncology medicines CAMBRIDGE , Mass . , Aug. 12 , 2021 ( GLOBE NEWSWIRE ) -- Relay Therapeutics , Inc. ( Nasdaq : RLAY ) , a clinical - stage precision medicine company transforming the drug discovery process by combining leading edge computational and experimental technologies , today provided an update on its PI3Ka mutant selective program , reported second quarter 2021 financial results and announced a collaboration with EQRX . " PI3Ka mutations have been a known oncogene for the past 20 years but this has been a very difficult drug discovery challenge to solve using conventional approaches . Leveraging our Dynamo ™ platform , the Relay Therapeutics team has been able to create what we believe to be the first ever mutant selective inhibitor of PI3Ka , which offers the potential to address a significant unmet medical need , ” said Sanjiv Patel , M.D. , president and chief executive officer . “ Other programs in our pipeline continue to progress as anticipated , with RLY - 4008 , our FGFR2 inhibitor on track for an initial data disclosure later this year . We hope to demonstrate that our platform has achieved another breakthrough by potentially creating the first ever selective small molecule inhibitor of FGFR2 . Finally , our new collaboration with EQRx announced today opens yet another avenue for our Dynamo platform to potentially impact the lives of more patients and generate value for our shareholders . This partnership allows us to utilize the scale and efficiencies of our machine learning and artificial intelligence capabilities against an expanded target landscape . We look forward to a productive remainder of 2021. " PI3Ka Mutant Selective Program Update Phosphoinositide 3 - kinase alpha ( PI3Ka ) is the most frequently mutated kinase in solid tumors . Approximately 60 % -70 % of the mutations in PI3Ka cluster at three amino acids ( H1047 , E542 , and E545 ) . Traditionally , the development of PI3Ka inhibitors has focused on the active , or orthosteric site . The therapeutic index of orthosteric inhibitors is limited by the lack of clinically meaningful selectivity for mutant versus wild - type PI3Ka and off - isoform activity . Toxicity related to inhibition of wild - type PI3Ka and other PI3K isoforms results in sub - optimal inhibition of mutant PI3Ka with reductions in dose intensity and frequent discontinuation . RLY - 2608 , the first allosteric , pan - mutant ( H1047X , E542X and E545X ) , and isoform - selective PI3Ka inhibitor was designed to overcome these limitations . Relay Therapeutics solved the full - length cryo - EM structure of PI3Ka , performed computational long time - scale molecular dynamic simulations to elucidate conformational differences between wild - type and mutant PI3Ka , and leveraged these insights to enable the design of RLY - 2608 . In biochemical assays , RLY - 2608 inhibits H1047R , E542K , and E545K mutant PI3Ka activity with < 10nM potency and 8-12x selectivity relative to wild - type PI3Ka . RLY - 2608 is > 1000 - fold selective over the ẞ , ō , and y PI3K isoforms in biochemical assays and demonstrates exquisite selectivity across a panel of 322 kinases . This progress puts RLY - 2608 on path to initiate a first - in - human clinical study in the first half of 2022. RLY - 2608 is the lead program of multiple preclinical efforts to discover and develop mutant selective inhibitors of PI3Ka . Strategic Collaboration with EQRX Relay Therapeutics and EQRX entered a worldwide strategic collaboration to discover , develop , and commercialize novel medicines against validated oncology targets . Under the terms of the agreement , Relay Therapeutics will be responsible for the discovery phase through to Investigational New Drug application filing , while EQRX will be responsible for clinical development , regulatory and commercialization efforts of the product candidates developed pursuant to the collaboration . Relay Therapeutics and EQRX will equally share in the discovery , development and commercialization costs and the net profits from sales of any collaboration medicines , if approved . The collaboration will start with one program , but the companies can mutually agree to add additional programs to the collaboration in the future . Relay Therapeutics retains the right to develop any collaboration medicines in combination with its wholly - owned pipeline . Other Recent Corporate Highlights • RLY - 4008 , a potent , selective and oral small molecule inhibitor of FGFR2 , remains on track to report initial safety , tolerability and pharmacokinetics data across multiple dose levels before the end of 2021. Most patients to be reported on will be FGFR2 altered cholangiocarcinoma ( CCA ) patients with prior exposure to pan - FGFR inhibitor therapies . The disclosure will also include preliminary efficacy data focusing on FGFR2 fusion CCA pan - FGFR treatment naïve patients . • In July 2021 , Genentech initiated the cohort of RLY - 1971 / GDC - 1971 , an inhibitor of SHP2 , in combination with GDC - 6036 , an inhibitor of KRAS G12C , in a Phase 1b trial .